/***************************************************************************/
/*                                                                         */
/*  ftdriver.h                                                             */
/*                                                                         */
/*    FreeType font driver interface (specification).                      */
/*                                                                         */
/*  Copyright 1996-2003, 2006, 2008, 2011 by                               */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#ifndef __FTDRIVER_H__
#define __FTDRIVER_H__


#include <ft2build.h>
#include FT_MODULE_H


FT_BEGIN_HEADER


typedef FT_Error
(*FT_Face_InitFunc)( FT_Stream stream,
                     FT_Face face,
                     FT_Int typeface_index,
                     FT_Int num_params,
                     FT_Parameter *parameters );

typedef void
(*FT_Face_DoneFunc)( FT_Face face );


typedef FT_Error
(*FT_Size_InitFunc)( FT_Size size );

typedef void
(*FT_Size_DoneFunc)( FT_Size size );


typedef FT_Error
(*FT_Slot_InitFunc)( FT_GlyphSlot slot );

typedef void
(*FT_Slot_DoneFunc)( FT_GlyphSlot slot );


typedef FT_Error
(*FT_Size_RequestFunc)( FT_Size size,
                        FT_Size_Request req );

typedef FT_Error
(*FT_Size_SelectFunc)( FT_Size size,
                       FT_ULong size_index );

#ifdef FT_CONFIG_OPTION_OLD_INTERNALS

typedef FT_Error
(*FT_Size_ResetPointsFunc)( FT_Size     size,
                            FT_F26Dot6  char_width,
                            FT_F26Dot6  char_height,
                            FT_UInt     horz_resolution,
                            FT_UInt     vert_resolution );

typedef FT_Error
(*FT_Size_ResetPixelsFunc)( FT_Size  size,
                            FT_UInt  pixel_width,
                            FT_UInt  pixel_height );

#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */

typedef FT_Error
(*FT_Slot_LoadFunc)( FT_GlyphSlot slot,
                     FT_Size size,
                     FT_UInt glyph_index,
                     FT_Int32 load_flags );


typedef FT_UInt
(*FT_CharMap_CharIndexFunc)( FT_CharMap charmap,
                             FT_Long charcode );

typedef FT_Long
(*FT_CharMap_CharNextFunc)( FT_CharMap charmap,
                            FT_Long charcode );


typedef FT_Error
(*FT_Face_GetKerningFunc)( FT_Face face,
                           FT_UInt left_glyph,
                           FT_UInt right_glyph,
                           FT_Vector *kerning );


typedef FT_Error
(*FT_Face_AttachFunc)( FT_Face face,
                       FT_Stream stream );


typedef FT_Error
(*FT_Face_GetAdvancesFunc)( FT_Face face,
                            FT_UInt first,
                            FT_UInt count,
                            FT_Int32 flags,
                            FT_Fixed *advances );


/*************************************************************************/
/*                                                                       */
/* <Struct>                                                              */
/*    FT_Driver_ClassRec                                                 */
/*                                                                       */
/* <Description>                                                         */
/*    The font driver class.  This structure mostly contains pointers to */
/*    driver methods.                                                    */
/*                                                                       */
/* <Fields>                                                              */
/*    root             :: The parent module.                             */
/*                                                                       */
/*    face_object_size :: The size of a face object in bytes.            */
/*                                                                       */
/*    size_object_size :: The size of a size object in bytes.            */
/*                                                                       */
/*    slot_object_size :: The size of a glyph object in bytes.           */
/*                                                                       */
/*    init_face        :: The format-specific face constructor.          */
/*                                                                       */
/*    done_face        :: The format-specific face destructor.           */
/*                                                                       */
/*    init_size        :: The format-specific size constructor.          */
/*                                                                       */
/*    done_size        :: The format-specific size destructor.           */
/*                                                                       */
/*    init_slot        :: The format-specific slot constructor.          */
/*                                                                       */
/*    done_slot        :: The format-specific slot destructor.           */
/*                                                                       */
/*                                                                       */
/*    load_glyph       :: A function handle to load a glyph to a slot.   */
/*                        This field is mandatory!                       */
/*                                                                       */
/*    get_kerning      :: A function handle to return the unscaled       */
/*                        kerning for a given pair of glyphs.  Can be    */
/*                        set to 0 if the format doesn't support         */
/*                        kerning.                                       */
/*                                                                       */
/*    attach_file      :: This function handle is used to read           */
/*                        additional data for a face from another        */
/*                        file/stream.  For example, this can be used to */
/*                        add data from AFM or PFM files on a Type 1     */
/*                        face, or a CIDMap on a CID-keyed face.         */
/*                                                                       */
/*    get_advances     :: A function handle used to return advance       */
/*                        widths of `count' glyphs (in font units),      */
/*                        starting at `first'.  The `vertical' flag must */
/*                        be set to get vertical advance heights.  The   */
/*                        `advances' buffer is caller-allocated.         */
/*                        The idea of this function is to be able to     */
/*                        perform device-independent text layout without */
/*                        loading a single glyph image.                  */
/*                                                                       */
/*    request_size     :: A handle to a function used to request the new */
/*                        character size.  Can be set to 0 if the        */
/*                        scaling done in the base layer suffices.       */
/*                                                                       */
/*    select_size      :: A handle to a function used to select a new    */
/*                        fixed size.  It is used only if                */
/*                        @FT_FACE_FLAG_FIXED_SIZES is set.  Can be set  */
/*                        to 0 if the scaling done in the base layer     */
/*                        suffices.                                      */
/* <Note>                                                                */
/*    Most function pointers, with the exception of `load_glyph', can be */
/*    set to 0 to indicate a default behaviour.                          */
/*                                                                       */
typedef struct FT_Driver_ClassRec_
{
    FT_Module_Class root;

    FT_Long face_object_size;
    FT_Long size_object_size;
    FT_Long slot_object_size;

    FT_Face_InitFunc init_face;
    FT_Face_DoneFunc done_face;

    FT_Size_InitFunc init_size;
    FT_Size_DoneFunc done_size;

    FT_Slot_InitFunc init_slot;
    FT_Slot_DoneFunc done_slot;

#ifdef FT_CONFIG_OPTION_OLD_INTERNALS

    FT_Size_ResetPointsFunc   set_char_sizes;
    FT_Size_ResetPixelsFunc   set_pixel_sizes;

#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */

    FT_Slot_LoadFunc load_glyph;

    FT_Face_GetKerningFunc get_kerning;
    FT_Face_AttachFunc attach_file;
    FT_Face_GetAdvancesFunc get_advances;

    /* since version 2.2 */
    FT_Size_RequestFunc request_size;
    FT_Size_SelectFunc select_size;

} FT_Driver_ClassRec, *FT_Driver_Class;


/*
 *  The following functions are used as stubs for `set_char_sizes' and
 *  `set_pixel_sizes'; the code uses `request_size' and `select_size'
 *  functions instead.
 *
 *  Implementation is in `src/base/ftobjs.c'.
 */
#ifdef FT_CONFIG_OPTION_OLD_INTERNALS

FT_BASE( FT_Error )
ft_stub_set_char_sizes( FT_Size     size,
                        FT_F26Dot6  width,
                        FT_F26Dot6  height,
                        FT_UInt     horz_res,
                        FT_UInt     vert_res );

FT_BASE( FT_Error )
ft_stub_set_pixel_sizes( FT_Size  size,
                         FT_UInt  width,
                         FT_UInt  height );

#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */

/*************************************************************************/
/*                                                                       */
/* <Macro>                                                               */
/*    FT_DECLARE_DRIVER                                                  */
/*                                                                       */
/* <Description>                                                         */
/*    Used to create a forward declaration of a                          */
/*    FT_Driver_ClassRec stract instance.                                */
/*                                                                       */
/* <Macro>                                                               */
/*    FT_DEFINE_DRIVER                                                   */
/*                                                                       */
/* <Description>                                                         */
/*    Used to initialize an instance of FT_Driver_ClassRec struct.       */
/*                                                                       */
/*    When FT_CONFIG_OPTION_PIC is defined a Create funtion will need    */
/*    to called with a pointer where the allocated stracture is returned.*/
/*    And when it is no longer needed a Destroy function needs           */
/*    to be called to release that allocation.                           */
/*    fcinit.c (ft_create_default_module_classes) already contains       */
/*    a mechanism to call these functions for the default modules        */
/*    described in ftmodule.h                                            */
/*                                                                       */
/*    Notice that the created Create and Destroy functions call          */
/*    pic_init and pic_free function to allow you to manually allocate   */
/*    and initialize any additional global data, like module specific    */
/*    interface, and put them in the global pic container defined in     */
/*    ftpic.h. if you don't need them just implement the functions as    */
/*    empty to resolve the link error.  Also the pic_init and pic_free   */
/*    functions should be declared in pic.h, to be referred by driver    */
/*    definition calling FT_DEFINE_DRIVER() in following.                */
/*                                                                       */
/*    When FT_CONFIG_OPTION_PIC is not defined the struct will be        */
/*    allocated in the global scope (or the scope where the macro        */
/*    is used).                                                          */
/*                                                                       */
#ifndef FT_CONFIG_OPTION_PIC

#ifdef FT_CONFIG_OPTION_OLD_INTERNALS
#define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_,b_) \
  a_, b_,
#else
#define FT_DEFINE_DRIVERS_OLD_INTERNALS( a_, b_ )
#endif

#define FT_DECLARE_DRIVER( class_ )    \
  FT_CALLBACK_TABLE                  \
  const FT_Driver_ClassRec  class_;

#define FT_DEFINE_DRIVER( class_, \
                         flags_, size_, name_, version_, requires_, \
                         interface_, init_, done_, get_interface_, \
                         face_object_size_, size_object_size_, \
                         slot_object_size_, init_face_, done_face_, \
                         init_size_, done_size_, init_slot_, done_slot_, \
                         old_set_char_sizes_, old_set_pixel_sizes_, \
                         load_glyph_, get_kerning_, attach_file_, \
                         get_advances_, request_size_, select_size_ )        \
  FT_CALLBACK_TABLE_DEF                                                      \
  const FT_Driver_ClassRec class_ =                                          \
  {                                                                          \
    FT_DEFINE_ROOT_MODULE(flags_,size_,name_,version_,requires_,interface_,  \
                          init_,done_,get_interface_)                        \
                                                                             \
    face_object_size_,                                                       \
    size_object_size_,                                                       \
    slot_object_size_,                                                       \
                                                                             \
    init_face_,                                                              \
    done_face_,                                                              \
                                                                             \
    init_size_,                                                              \
    done_size_,                                                              \
                                                                             \
    init_slot_,                                                              \
    done_slot_,                                                              \
                                                                             \
    FT_DEFINE_DRIVERS_OLD_INTERNALS(old_set_char_sizes_, old_set_pixel_sizes_) \
                                                                             \
    load_glyph_,                                                             \
                                                                             \
    get_kerning_,                                                            \
    attach_file_,                                                            \
    get_advances_,                                                           \
                                                                             \
    request_size_,                                                           \
    select_size_                                                             \
  };

#else /* FT_CONFIG_OPTION_PIC */

#ifdef FT_CONFIG_OPTION_OLD_INTERNALS
#define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_,b_) \
  clazz->set_char_sizes = a_; \
  clazz->set_pixel_sizes = b_;
#else
#define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_,b_)
#endif

#define FT_DECLARE_DRIVER(class_)    FT_DECLARE_MODULE(class_)

#define FT_DEFINE_DRIVER(class_,                                             \
                         flags_, size_, name_, version_, requires_,          \
                         interface_, init_, done_, get_interface_,           \
                         face_object_size_, size_object_size_,               \
                         slot_object_size_, init_face_, done_face_,          \
                         init_size_, done_size_, init_slot_, done_slot_,     \
                         old_set_char_sizes_, old_set_pixel_sizes_,          \
                         load_glyph_, get_kerning_, attach_file_,            \
                         get_advances_, request_size_, select_size_ )        \
                                                                             \
  void                                                                       \
  FT_Destroy_Class_##class_( FT_Library        library,                      \
                             FT_Module_Class*  clazz )                       \
  {                                                                          \
    FT_Memory       memory = library->memory;                                \
    FT_Driver_Class dclazz = (FT_Driver_Class)clazz;                         \
    class_##_pic_free( library );                                            \
    if ( dclazz )                                                            \
      FT_FREE( dclazz );                                                     \
  }                                                                          \
                                                                             \
  FT_Error                                                                   \
  FT_Create_Class_##class_( FT_Library        library,                       \
                            FT_Module_Class**  output_class )                \
  {                                                                          \
    FT_Driver_Class  clazz;                                                  \
    FT_Error         error;                                                  \
    FT_Memory        memory = library->memory;                               \
                                                                             \
    if ( FT_ALLOC( clazz, sizeof(*clazz) ) )                                 \
      return error;                                                          \
                                                                             \
    error = class_##_pic_init( library );                                    \
    if(error)                                                                \
    {                                                                        \
      FT_FREE( clazz );                                                      \
      return error;                                                          \
    }                                                                        \
                                                                             \
    FT_DEFINE_ROOT_MODULE(flags_,size_,name_,version_,requires_,interface_,  \
                          init_,done_,get_interface_)                        \
                                                                             \
    clazz->face_object_size    = face_object_size_;                          \
    clazz->size_object_size    = size_object_size_;                          \
    clazz->slot_object_size    = slot_object_size_;                          \
                                                                             \
    clazz->init_face           = init_face_;                                 \
    clazz->done_face           = done_face_;                                 \
                                                                             \
    clazz->init_size           = init_size_;                                 \
    clazz->done_size           = done_size_;                                 \
                                                                             \
    clazz->init_slot           = init_slot_;                                 \
    clazz->done_slot           = done_slot_;                                 \
                                                                             \
    FT_DEFINE_DRIVERS_OLD_INTERNALS(old_set_char_sizes_, old_set_pixel_sizes_) \
                                                                             \
    clazz->load_glyph          = load_glyph_;                                \
                                                                             \
    clazz->get_kerning         = get_kerning_;                               \
    clazz->attach_file         = attach_file_;                               \
    clazz->get_advances        = get_advances_;                              \
                                                                             \
    clazz->request_size        = request_size_;                              \
    clazz->select_size         = select_size_;                               \
                                                                             \
    *output_class = (FT_Module_Class*)clazz;                                 \
    return FT_Err_Ok;                                                        \
  }


#endif /* FT_CONFIG_OPTION_PIC */

FT_END_HEADER

#endif /* __FTDRIVER_H__ */


/* END */
